Field of the Invention
The present invention is related to methods and apparatuses for bending light guides for guiding light emitted by light emitting diodes (LEDs).
Description of the Related Art
Glass tubes filled with neon gas have been used to provide decorative, colored lights. For example, U.S. Pat. No. 5,001,613 describes a housing to protect neon tube lights. This is necessary because the glass tubes are fragile. Further, neon tube lights are difficult and costly to manufacture. Finally, neon tube lights consume a significant amount of power, and thus are costly to keep lit. Accordingly, alternative decorative lighting devices were desired.
The invention of LEDs allowed a low cost alternative to neon lighting. With regard to the power consumed, LEDs consume only 10% or less of a comparable neon tube light. However, the light from an LED needs to pass through a light guide to provide the same effect as a neon tube. To provide the same versatility as neon tubes, the light guides need to be able to be formed into a plurality of shapes, especially lettering. Conventionally, this has been done by heating a plastic light guide with a heat gun and then bending the hot light guide. However, this process is time consuming, difficult to repeat, and cannot provide light guides with a radius of curvature comparable to neon tubes.